SoqlXplorer

DevAngel's
AppExchange Explorer is an invaluable tool when
working with the Salesforce.com API, but I've been recently chaffing that there's no OSX version, so I fixed that.
You can explore the object & field describes results, build & run SOQL queries,
edit data, run apex code, it even do syntax highlighting on the query as you edit it along with a graphical schema explorer.

New in v0.90, support for SOQL-R queries, queries that have child queries now show the magnifying glass icon and row count in the main query results. double click
the magnifying glass to show the child query results in the 2nd query results view at the bottom of the window.

right click on any row to have the option to open that row in the browser

for queries that include the Id column, you can click on data cells to edit them and update salesforce.com

open the Recent Queries List window from the menu to see your last 10 executed queries, click on any of them to copy their text to the SOQL window.

Syntax highlighting in action

Graphical schema explorer

Use the +/- buttons to expand/contract the list of fields shown for a particular SObject. double click any SObject to make it the center focus (or select it from the SObject list on the right).

To generate a schema report, right click on an object name from the list, once the report window has opened, you can print the report, or save it to a PDF.

Download

As of v2.2, SoqlXplorer requires Mountain Lion (OSX v10.8). Download SoqlXplorer_v2.20.zip and give it a go.

If you're still on Lion (10.7), you can still download the latest version that works on Lion, download SoqlXplorer_v2.00.zip.
If you're still on Snow Leopard (10.6), you can still download the latest version that works on SL, download SoqlXplorer_v1.70.zip.
If you're still on Leopard (10.5), you can still download the last version that works on Leopard, download SoqlXplorer_v1.60.zip.
If you're still on Tiger (10.4), you can still download the last version that works on Tiger, download SoqlXplorer_v0.84.zip.

Release History

v2.2, Oct 12, 2014

Updated to Salesforce API v32.0

Fixed schema drawing problems on OSX 10.9 and up.

v2.1, July 6, 2014

Updated to Salesforce API v31.0

Added option to sort fields by name in sidebar.

Added option to double click field name in sidebar to add/remove from query text.

Added keyboard shortcuts for Query ⌘R / All ⇧⌘R / More ⌘M

Added ability to change font size for query & apex text areas.

Fixed a bug that can cause the login window to not show in some circumstances.

v2.00, Feb 18, 2014

Updated to Salesforce API v30.0

Added option to sort fields by name in auto generated queries.

Added support for showing the members of the new compound field types in the query results (e.g. location & address)

Added option to control which fields are added to auto generated queries for compound fields

Object icons now appear in various places, including the schema views, and the object list.

v1.94, Oct 30, 2013

Updated to Salesforce API v29.0.

Shows organizational API usage count in bottom right of footer.

Signed with a developerId to keep gatekeeper happy.

v1.93, Jun 27, 2013

Requires OSX 10.7 or later.

Updated to Salesforce API v28.0 (aka Summer '13)

v1.92, Feb 5, 2013

Requires OSX 10.7 or later.

Update for Salesforce API v27.0 (aka Spring '13)

Fixed crash where "Check for updates" with no window open would cause a crash.

v1.91, Dec 22, 2012

Requires OSX 10.7 or later.

Fixed issue with login server names missing for clean installs.

Reverted details/recents panel windows to previous style where they are not attached to the main window to stop them getting hidden under the main window.

v1.9, Oct 16, 2012

Requires OSX 10.7 or later.

Fixed crash when doing SOQL-R queries on a 64bit machine.

Fixed bug with version fallback not working.

Fixed layout issue with schema report window when its resized.

v1.8, Oct 8, 2012

Requires OSX 10.7 or later.

Multiple login/window support, just goto File->Login and have as many windows/logins open at once as you'd like.

Can now run searches as well as queries, just type your sosl search into the query box just like you would a soql query.

Updated to newer version of Sparkle, future updates will be cryptographically verified by the updater.